Merge pkg_install-20090201 from pkg_install-renovation branch.
- DB support is always included from libnbcompat if needed
- pkg_view and linkfarm are not installed any more; they are not moved
into the attic yet, so they can easily be installed as separte package
- common configuration file to customise the behavior of various
components; this supersedes the old audit-packages.conf
- support for PKSC7 signatures (using X509 certs) and GPG signatures for
packages in a secure way. See pkg_admin(8) for how to create them and
pkg_install.conf(5) for the options to use them
- audit-packages and download-vulnerability-list are wrapper scripts
around pkg_admin. They try to mimic the classic options if used sanely.
"pkg_admin audit" is now an order of magnitude faster than before
- pkg_add uses libarchive and libfetch instead of external ftp and tar:
- progress bar is currently missing for downloads
- "pkg_add -" is no longer supported
- no adhoc check for conficts between dependencies and already
installed packages
- "pkg_add -s" has been replaced with an option in pkg_install.conf,
verification of plain detached GPG signatures is no longer supported
- optional check for vulnerabilities before adding a package
- if /var and /usr/pkg are on different fileystems it is twice as fast
now
- conflicts due to overlapping plists are checked before installation
- pkg_add no longer plays with the process limits
- pkg_add and pkg_delete have a new destdir option; scripts have to
either be modified to use PKG_DESTDIR or should be disabled
- pkg_add -u for now can't be used to update to the exact same version
- internal "rm -rf" and "mkdir_p" code
- all memory allocation failures are not explicitly fatal
- if a file is not removed due to a failed checksum, still remove the
entry from pkgdb

pkg_install-20080524:
Stop installation the pkg_view and linkform script as part of
pkg_install. They are the only remaining user of the pax dependency.
This was discussed was agc@ and the consensus is that if someone really
wants them, they should be pulled into a separate less essential
package.

Change download-vulnerability-list.sh to use exec_prefix in the
sense of pkg_tools_prefix and prefix in the sense of LOCALBASE.
This allows individual overriding for NetBSD.
Add the forgotten part to allow DESTDIR builds and the pkgsrc.7 man
page.

Sync with src, version 20060424:
Add support for creating summary file containing all information
about a package repository needed by package managing software.
This allows better use of remote binary package repositories.
Discussed on tech-pkg.

Remove @exec from PLIST and put the action into an INSTALL script instead.
Also, simplify the package by making use of the PKGMANDIR-handling in
pkgsrc to remove the custom MANDIR code from the package Makefile and
the PLIST.
Technically, this type of a change would require a PKGREVISION bump,
but as this is the pkg_* tools package and there were no changes to the
binaries, we refrain from doing so.

Update pkg_install to 20030823, which has the changes to support
package views. Pkgsrc changes include:
* Convert to use pkgtools/libnbcompat so that it's easier to keep
this in sync with src/usr.sbin/pkg_install.
* Add a src2nbcompat script that converts src/usr.sbin/pkg_install
into an appropriate start for pkgtools/pkg_install. The script
removes the Makefiles, adds CPP inclusion guards around each
#include <...> line, and includes <nbcompat.h> at the top of each
*.c file. This should make it even easier to keep sources in
sync with the HEAD.